1/*
2 * Copyright (c) 2013 Andreas Sandberg
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Andreas Sandberg
29 */
30
31#include "arch/generic/mmapped_ipr.hh"
32
33#include "arch/isa_traits.hh"
34#include "config/the_isa.hh"
35#include "mem/packet.hh"
36#include "mem/packet_access.hh"
37#include "sim/pseudo_inst.hh"
38
39using namespace GenericISA;
40
41static void
42handlePseudoInst(ThreadContext *xc, Packet *pkt)
43{
44    const Addr offset(pkt->getAddr() & IPR_IN_CLASS_MASK);
45    const uint8_t func((offset >> 8) & 0xFF);
46    const uint8_t subfunc(offset & 0xFF);
47    uint64_t ret;
48
49    assert((offset >> 16) == 0);
50    ret = PseudoInst::pseudoInst(xc, func, subfunc);
51    if (pkt->isRead())
52        pkt->set(ret, TheISA::GuestByteOrder);
53}
54
55Cycles
56GenericISA::handleGenericIprRead(ThreadContext *xc, Packet *pkt)
57{
58    Addr va(pkt->getAddr());
59    Addr cls(va >> IPR_CLASS_SHIFT);
60
61    switch (cls) {
62    case IPR_CLASS_PSEUDO_INST:
63        handlePseudoInst(xc, pkt);
64        break;
65    default:
66        panic("Unhandled generic IPR read: 0x%x\n", va);
67    }
68
69    return Cycles(1);
70}
71
72Cycles
73GenericISA::handleGenericIprWrite(ThreadContext *xc, Packet *pkt)
74{
75    Addr va(pkt->getAddr());
76    Addr cls(va >> IPR_CLASS_SHIFT);
77
78    switch (cls) {
79    case IPR_CLASS_PSEUDO_INST:
80        handlePseudoInst(xc, pkt);
81        break;
82    default:
83        panic("Unhandled generic IPR write: 0x%x\n", va);
84    }
85
86    return Cycles(1);
87}
88